Degreeing a cam is done for two reasons:
1. Quality assurance. How do you know that all the lobes have been ground at the proper position relative to each other and relative to the crank position? What if the cam grinder was having a bad day (hung-over on Monday) or the CNC computer developed a glich when it was grinding your cam and ground the intakes off the exhaust master or vice-versa.

2. Establishing a baseline. If you're going to maximize your cam timing in this motor, you need to know where you're starting from before you go advancing or retarding the cam so you can keep records of valve timing events and the results of your changes.

If you don't plan to make any changes after the motor is running, put the cam in on the factory timing marks and hope for the best.